(a) Field of the Invention
The present invention relates to an apparatus for coloring, decoloring and drying sample carriers in electrophoretic systems.
(b) Description of the Prior Art
The electrophoresis is utilized for measuring proteins contained in blood serum in clinical inspection laboratories, etc. of hospitals and medical institutes. For the electrophoresis, blood serum to be analyzed is applied onto a carrier which is made of cellulose acetate or the similar material and then the carrier is electrically energized for developing fractionated patterns of the blood serum. The carrier is colored with a coloring liquid agent and, after the area other than the blood serum is decolored, the sample is subjected to colorimetry for quantitative determination. Conventionally, various processes of this analysis were manually carried out with low efficiency. Further, analysis by the electrophoresis required highly delicate skill and the conventional electrophoretic system had a defect that analytical results were different depending on individual analysts' measuring skills. In view of such circumstances, there have hitherto been developed automatic electrophoretic systems which can automatically carry out the processes of the electrophoresis for the purpose of enhancing measuring efficiency and eliminating analytical variations due to difference in measuring skills depending on individual analysis. As an apparatus to carry out the coloring, decoloring and drying processes out of the various steps of the electrophoresis, there has been known an apparatus disclosed by Japanese published unexamined Utility Model No. 158694/54. This coloring-decoloring-drying apparatus is designed in such a manner that a carrier is bonded onto circumference of a drum, rotated therewith so as to pass through a liquid container filled with a coloring or decoloring liquid agent for coloring and decoloring said carrier and, after the carrier is decolored, it is dried by exposing it to hot air blast or the similar means. An outline of this coloring-decoloring-drying apparatus will be described with reference to FIG. 1. A carrier 1 onto which fractionated patterns of a sample have been developed in an electrophoretic apparatus (not shown) is fed between a roller 2 and a drum 3 by an adequate means. The carrier which is soaked with a buffer solution is thus bonded onto the drum 3 consecutively from the leading end of said carrier. When the leading end of the carrier has passed just beyond another roller 4, rotation of the drum 3 is stopped so that the carrier 1 is held in the condition where it is bonded onto the outer circumference of the drum 3 while being held with both the rollers 2 and 4. In this condition, the drum 3 is rotated together with the rollers 2 and 4 so that the carrier 1 is rotated while it is bonded onto the drum 3 and held with the rollers 2 and 4. A liquid container 5 is filled with a coloring liquid agent, and therefore the carrier is colored since it passes through the liquid agent during its rotation. The carrier is decolored in the similar way when the container is filled with a decoloring liquid agent instead of the coloring liquid agent. After the carrier has been colored and decolored as described above, it is dried with a hot air blast supplied from a blower port (not shown), and then the drum 3 only is rotated to feed the carrier 1 to the next process. The coloring-decoloring-drying apparatus described above has a surface 3a having a curvature lower than the imaginary circular circumference of the drum 3 which serves for preventing the carrier 1 from being torn due to contraction at the drying process. Since degree of the contraction is different depending on materials of the carrier, curvature of the surface should ideally be varied depending on contraction degree of the carrier. Further, when the carrier has a short length, it is required to use a drum having a small diameter. In such a case, the carrier bonded onto the drum is held in a strongly curved condition and such a curved form remains at the subsequent processes, thereby causing inconvenience at the processes after the coloring and decoloring. Moreover, the drum type of apparatus shown in FIG. 1 has a drawback in that it has a very complicated mechanism and requires a large number of parts.